Skin seal with inflatable membrane

ABSTRACT

A skin seal or trocar stabilizer with an inflatable balloon in the shape of a dumbbell, where the balloon may be stored within a cannula for easy placement in an incision and inflated to deploy the balloon inside the body, and a portion of the balloon expands inside the cannula, whereby medical instruments may be passed through the skin seal into a laparoscopic workspace while the balloon is inflated, thereby allowing the use of normal short surgical instruments during laparoscopic procedures and during insufflation.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. application Ser. No.08/867,285, filed on Jun. 2, 1997, now U.S. Pat. No. 5,964,781, which isa continuation of U.S. application Ser. No. 08/444,425, filed on May 19,1995, now U.S. Pat. No. 5,634,937. The priority of these priorapplications is expressly claimed and their disclosures are herebyincorporated by reference in their entirety.

FIELD OF THE INVENTION

This invention relates to the field of surgical endoscopy, specificallyto improvements in skin seals and cannulas.

BACKGROUND OF THE INVENTION

Surgical endoscopy is a surgical technique of using small diameterlong-handled tools such as graspers, forceps, scissors, refractors,dissectors, and clamps specially designed to be inserted through smallincisions in the skin (or other openings in the body) to performoperations within the body. The surgeon performing the surgery oftencannot see the operation directly and must watch the procedure on avideo monitor fed by an endoscopic camera or endoscope. Endoscopicsurgery replaces open surgery that requires large incisions, essentiallyopening the body cavity completely, in order to perform surgery deepwithin the body. Endoscopic techniques have been used for gall stoneremoval, gall bladder removal, hernia repair, tumor removal, lymph noderemoval, appendectomy, and many other operations. Endoscopic surgery isalso called laparoscopic surgery, video assisted surgery, minimallyinvasive surgery, and bandaid surgery, but throughout this specificationthe term endoscopic surgery or laparoscopic surgery will be used.

To illustrate the background of the inventions described below, theexample of the laparoscopic cholecystectomy, hernia repair, orlymphadenectomy, as well as the operation for harvesting a blood vessel,will be used to illustrate both the old laparoscopic procedures and thenew laparoscopic procedures now possible with the new devices. In theold procedure, a working space was created in the abdomen using theprocess called pneumoperitoneum or insufflation. Insufflation is theprocess of injecting gas into the body to blow it up like a balloon,creating a chamber filled with gas. When performed on the abdomen, theperitoneum is inflated and the procedure is known as pneumoperitoneum.The procedure can be used for inflating a space between the peritoneumand the skin to permit laparoscopic hernia repair, as illustrated inU.S. Pat. No. 5,496,345, issued to Kieturakis et al. and entitled “AnExpansible Tunneling Apparatus for Creating an Anatomic Working Space.”Insufflation can be used also to inflate a tunnel shaped working spaceover a blood vessel, to facilitate blood vessel harvesting, as describedin U.S. patent application Ser. No. 08/267,484, entitled “ExtraluminalBalloon Dissection Apparatus and Methods,” incorporated herein byreference. While the chamber is filled with gas, the surgeon insertslong slender laparoscopic tools through trocars and cannulas that piercethe skin and provide access ports into the insufflated chamber.

For abdominal surgery, such as a cholecystectomy, (gall bladderremoval), the insufflation is accomplished by the following procedure.An incision is made at the lower edge of the belly button or umbilicus.The surgeon uses his fingers or a blunt dissection tool, such as a bluntnosed obturator, to uncover the fascia or abdominal muscles, then alarge needle, referred to as a Verres needle, is inserted into theabdomen or peritoneal cavity. The Verres needle punctures the fascia andperitoneum that cover the abdomen. A pressurized gas such as CO₂ isinjected into the abdomen through the needle, in effect inflating theabdomen like a balloon. After the abdomen is inflated, the Verres needleis removed. After the needle is removed, trocars and cannulas areinserted into the space created by the insufflation. Endoscopicinstruments, including an endoscope or laparoscope, scissors, graspers,etc., are inserted into the abdomen through the cannulas and manipulatedto dissect tissue surrounding the gallbladder, remove the gall bladder,and stitch the internal wounds.

To harvest the saphenous vein using laparoscopic procedures, the surgeonmay insufflate a tunnel shaped workspace over a blood vessel. The tunnelis first created using obturators, tunneling devices, or balloonsinserted through small incisions along or over the saphenous vein. Afterthe tunnel is created, the surgeon may insert skin seals and cannulas,and insufflation gas is injected through one of the trocars. While thetunnel is insufflated, the cannulas permit the surgeon to insertlaparoscopic instruments into the tunnel to perform surgery on thesaphenous vein.

The cannula used in the procedures described above is a length of rigidtube. The trocars and cannula are designed to allow laparoscopicinstruments to pass through them and prevent gas from escaping theabdomen or other insufflated work space. The cannula may have a flappervalve or a trumpet valve inside that opens to allow an endpscope,laparoscope, or other instrument to pass through, and the valve closeswhen the laparoscope is removed. Some trocar/cannula devices alsocontain a duckbill valve to assist in sealing the trocar. The cannulasare typically about 6 inches or 15 centimeters long, and come indiameters matching various laparoscopic devices, generally from 2 to 15mm.

Some surgeons use bare cannulas, secured only by a tight fit with theskin and fascia. However, cannulas frequently slip out of the bodyduring use, disrupting the procedure and possibly endangering thepatient. To prevent this danger, surgeons have devised a variety ofmethods to secure the cannula to the body and prevent it from slippingout of the body. Some cannulas are provided with threaded sleeves fixedto the cannula. Some cannulas are provided with a threaded gripper witha smooth inner bore that matches the size of the cannula, so that thecannula can slide inside the gripper as shown in FIG. 2. The gripperstabilizes the cannula so that it will not slip out of the bodyinadvertently, but can be easily slipped out when the surgeon wants. Thethreaded gripper is simply screwed into the incision in the skin. Thisoption permits the ready insertion and removal of smooth walled cannulasby sliding them in and out of the gripper. Other grippers have beenused, such as the gripper with expandable arms, the gripper withinflatable balloon on the outside, and the Hasson cannula. These devicesare illustrated in Oshinsky, et al., Laparoscopic Entry and Exit,reprinted in Urologic Laparoscopy at 91-101 (Das & Crawford ed. 1994).These devices are variously referred to as threaded skin seals, screwskin seals, skin anchors, obturators, grippers, trocar stabilizers, orcannula stabilizers.

The surgeon usually needs to place several trocars and cannulas into theabdomen and inserts as many as needed to accomplish the intendedoperation. The first cannula placed through the belly button is used toinsert a laparoscope so that the placement of other trocars and cannulascan be viewed from inside the abdomen. After several cannulas are inplace, the surgeon can view the procedure through any port and caninsert laparoscopic scissors, cutters and graspers, and other toolsthrough the cannulas in order to perform the surgery. The typicalendoscopic graspers 3 used for stitching inside the abdomen are shown,deployed inside the cannulas, in FIG. 2. A bare cannula 4 is used withendoscopic graspers 3 a. Another pair of laparoscopic graspers 3 b isinserted into a cannula 4 a that is inserted through a threaded gripper5. A third cannula 6, shown with a threaded outer surface, is providedfor an endoscope 34 that is inserted into the workspace to provide thesurgeon with a video view of the graspers 3 a and 3 b and body tissue.

The arrangement of the cannulas and trocars is required because theabdomen must be inflated to make room for the surgeon to work. The smalldiameter of the cannulas keeps the incisions small, and the matchingdiameter of the laparoscopic instruments is necessary to prevent leakageof the insufflation gas from the abdomen. Laparoscopic instruments ofvarious designs are available, and they generally are about 5 to 12 mmin diameter (to match the inside bore of the cannulas) and about 10 to40 cm in length. They are long and therefore difficult to use, and theyare usually used when the surgeon can see them only through thelaparoscope. Modern laparoscopic procedures require the surgeon to viewthe procedure on a video monitor. It may take a surgeon a lot ofpractice before becoming comfortable and skillful with the laparoscopicgraspers, grippers, and scissors. These tools are more difficult to usethan the surgical tools that every surgeon uses in normal surgery, suchas those shown in FIG. 3, in use during open laparotomy. The normalgraspers are shown in use while the surgeon is tying off a suture. Thisnormal procedure is familiar to a large number of surgeons. The normalsurgical graspers 7 a and 7 b are shown in use in FIG. 3, suturing bodytissue 8 with suture 9, and it can readily be appreciated that thelaparoscopic graspers shown in FIG. 2 require significantly more skillthan the normal surgical tools. One of the drawbacks of the knowncannulas and grippers is that they are adapted to admit only relativelynarrow instruments, and are therefore generally unsuited for use withordinary open incision surgical tools.

It would be advantageous to use normal surgical tools duringlaparoscopic procedures, but this is usually not permitted by thetypical construction of the trocars and cannulas that are too narrow,long, and rigid to permit passage of the normal surgical tools. Mostsurgeons are very well trained in using conventional nonendoscopicinstruments, such as the open incision graspers shown in FIG. 3, andnumerous procedures involving the graspers such as tying off a sutureare well known and well practiced. The endoscopic instruments shown inFIG. 2, on the other hand, are not well known and well practiced, andgenerally require significantly more skill than the more familiar openincision instruments. Thus, there is a need to provide cannulas andgrippers that would accommodate the instruments used in open incisionprocedures.

SUMMARY OF THE INVENTION

In a typical endoscopic or laparoscopic operation, a surgeon creates aworking space inside the body through insufflation. To create theworking space for abdominal surgery, the surgeon makes a small incisionat, for example, the inferior margin of the umbilicus 1 as shown in FIG.1, and then uses his fingers or a dissecting tool, such as a blunt nosedobturator, to prepare a point of injection. The surgeon then inserts aVerres needle 2 into the abdominal cavity, and causes a pressurized gassuch as CO₂ to flow through the needle and into the abdominal cavity.This inflates the abdomen, as shown in FIG. 1, and provides a workingspace for the surgeon. The needle may then be removed, and a cannula ortrocar/cannula combination may be inserted into the incision. Additionalincisions may also be made, and the first incision may be used to inserta laparoscope to assist in the placement of the other incisions. Theadditional incisions may each receive a cannula and, once severalcannulas are in place, the surgeon can view the procedure and/or insertlaparoscopic scissors, cutters, graspers, or other tools through any ofthe cannulas.

As mentioned above, the trocars and cannulas can be used in endoscopicblood vessel surgery, laparoscopic cholecystectomy, and laparoscopichernia repairs where a workspace is created under the skin. In the bloodvessel harvesting operation where the saphenous vein is to be removed, asurgeon creates a tunnel between two small incisions over the saphenousvein. Then a cannula and skin seal are inserted into each incision. Thetunnel is insufflated through one of the cannulas. In these procedures,the laparoscopic instruments are also inserted into the working spacethrough the cannulas, and the surgeon can watch the surgery through alaparoscope inserted through one of the cannulas.

The devices presented herein allow for use of normal surgical tools(such as the forceps and scissors used in open incision surgery) inlaparoscopic procedures. The skin seal is fitted with one or moreballoons on the inner bore. These balloons can be inflated after theskin seal is inserted into the incision into the abdomen Placement ofthe skin seal can be accomplished as usual, with the aid of a blunt orsharp trocar or cannula placed within the threaded skin seal. Thethreaded skin seal can be made of rigid plastic, as is customary, orpreferably it may be made of soft and pliable material such as latex orsilicone rubber. When the threaded skin seal is in place, the trocar maybe removed and the balloon may be inflated until it expands to fill theinner bore of the threaded skin seal, thus sealing the bore to maintainthe pressure created inside the abdomen with the insufflation gas. Theballoons are soft and pliable and can conform around the elements of theinstruments as they are moved about during use. Thus, normal orconventional surgical instruments may be passed between the balloons.Both normal surgical instruments and laparoscopic instruments may beinserted into the body through the balloons without disrupting the sealcreated by the balloons. The balloon is soft and pliable so that normalsurgical tools may be operated inside the inflated balloon segments, andthe balloon segments will not hamper the operation of the tool to asignificant degree. The skin seal may be provided with a balloonmembrane that expands outside the lumen of the skin seal to create adumbbell, dog bone, or bowtie shaped balloon which pinches the skin and,when necessary, fills the lumen of the skin seal.

More than one tool may be inserted through a single skin seal becausethe balloons are sufficiently pliable and may be inflated to a lesserdegree. In this manner, normal surgical instruments may be used inlaparoscopic procedures, taking advantage of the fact that they areeasier to use and more surgeons know how to use them, compared to thelong laparoscopic instruments. The balloon filled skin seal may be usedalso as a seal for laparoscopic incisions which are no longer necessaryor which the surgeon desires to plug temporarily while still leaving askin seal in place for later use.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external view of the abdomen of a patient undergoinginsufflation.

FIG. 2 is a cross section drawing of the insufflated abdomen of apatient with several trocars, cannulas and laparoscopic instruments inplace for a laparoscopic procedure.

FIG. 3 is a view of an open laparotomy procedure using normal surgicalforceps.

FIG. 4 is an exploded view of a cannula with an inflatable ballooninside.

FIG. 5 is a cross sectional view of the cannula with the inflatableballoon inside.

FIGS. 6, 6 a and 6 b show cross sectional views of the cannula with theinflatable balloon shown in its inflated state.

FIGS. 7 through 7c show end views, from the proximal end, of the cannulawith inflatable balloon inside.

FIGS. 8 shows a pair of skin seals with the balloons inside, with normalsurgical instrument inserted through the balloons, deployed in themanner of intended use.

FIG. 9 shows a blunt obturator suited for use with the skin seal.

FIG. 10 shows a sharp trocar type obturator suited for use with the skinseal.

FIG. 11 shows the blunt obturator inserted in the skin seal.

FIG. 12 shows a skin seal with balloons that expand outside the lumen ofthe skin seal.

FIG. 13 shows a cross section of the skin seal with outer balloon.

FIG. 14 shows an alternate embodiment of a skin seal with balloons whichexpand outside the lumen of the skin seal.

FIG. 15 shows an exploded view of the skin seal with outer balloons

FIG. 16 shows the skin seal with outer balloon prepared for insertioninto a skin incision.

FIGS. 17 through 17b show the skin seal with outer balloon inserted intoa skin incision.

FIG. 18 shows an alternate embodiment of the skin seal.

DETAILED DESCRIPTION OF THE DRAWINGS

The cannulas and grippers described below allow for use of normalsurgical instruments in laparoscopic surgical procedures. The typicalgripper configuration is modified by adding a balloon or inflatablemembrane to the inner bore of the gripper and adding an inflation portto the wall of the gripper to allow for inflation of the balloon. Whenthe balloon is inflated, it closes off the inner bore of the gripper sothat it provides an airtight seal during insufflation. The balloon ispliable so that tools can be inserted through the inner bore of theballoon, and the balloon expands around the surgical tool to maintainthe seal with little or no leakage of insufflation gas.

Referring to FIG. 4, the threaded skin seal 10 is made of a funnel ortube 11 with a generally conical or frustum outer shape with screwthreads 12 provided on the outer surface 13. The inner bore 14 isconical or funnel shaped, conforming generally to the shape of the outershape. Overall, the skin seal is funnel shaped, and the proximal end 15of the threaded skin seal has a large opening, and the distal or bottomend 16 has a smaller opening. The distal or bottom portion 16 of thethreaded skin seal may have a straight or cylindrical bore to provide atight fit with cannulas that have an outer diameter matching the innerdiameter of this straight bore. The distal or bottom portion of the skinseal may have a straight or cylindrical outer shape to make it easier toscrew the skin seal into an incision, and this straight section may bemade of variable length to match the different thickness of fat whichwill be encountered in different patients. The proximal end preferablyhas a conical inner bore to facilitate insertion of tools into theopening and through the cannula, but the inner bore may be straight. Theproximal end may also be described as flared and may be gradually flaredin relation to the distal end, as though trumpet shaped, or flared indiscrete fashion as in a typical funnel, with a straight tube at distalend and a conical segment at the proximal end. The screw threadsconstitute a fastening means, and may be replaced with other fasteningmeans such as a circumferentially ribbed outer contour or alongitudinally grooved outer contour. As shown, a flange 19 may beprovided on the proximal end of the cannula for ease in handling. Theflange 19 also provides a convenient means for mounting the bellows ontothe cannula. The skin seal is preferably 1 to 3 inches or about 2 to 8centimeters long.

A balloon membrane 20 has a generally conical or frustum shape matchingthe inner bore of the threaded skin seal and having the same overalllength of the threaded skin seal. The balloon membrane fits inside thethreaded skin seal and is sealed to the skin seal funnel at the upperedge and lower edge of the balloon membrane. The balloon membrane may beshorter than the skin seal, and may be sealed to the inner surface ofthe skin seal at points inside the skin seal, rather than at theimmediate distal and proximal edges of the skin seal. Also, the balloonmembrane may be longer than the skin seal and may be cuffed or foldedback around the outside of the skin seal at the proximal and distal endsand sealed at the cuffs.

An inflation port 21 is provided comprising a hole in the wall 22 of thethreaded skin seal. An inflation tube 23 or Luer fitting connects theinflation port to a suitable pump such as the syringe 24 shown in FIG. 5or the squeeze pump 25 shown in FIG. 6. Where the syringe is used, themembrane may be inflated and deflated repeatedly by pushing and pullingon the syringe plunger 26, thus forcing air into the bladder and suckingair out of the bladder. A one-way valve or stopcock may be used to sealthe membrane so that the pump or syringe may be detached from the skinseal for more convenient use. Alternately, an inflation port can beprovided at the distal tip of the skin seal, comprising an open airwaybetween the inflatable membrane and the insufflated workspace. In thismanner, the insufflation gas enters the skin seal from inside the bodyto pressurize and inflate the inflatable membrane. In this manner, anautomatic seal is created upon insertion of the skin seal into theinsufflated space. This simplifies placement and use of the skin sealbecause there is no need for a separate syringe or pump to inflate themembrane.

In the preferred embodiment, the bladder 20 is made of biocompatableelastomeric or elastic material, such as latex, silicone rubber, or anyother suitable compliant material, elastic material, or inflatablematerial. The cannula 10 is made of rigid or flexible material, soft orhard plastic, high density or low density polyethylene, polypropylene,thick latex, silicone rubber, or any other suitable material includingplastic, elastic, or nonelastic biocompatable material.

As shown in FIGS. 4 and 5, the inflatable skin seal may be constructedby applying an elastic cylindrical or conical balloon membrane 20 to theinner bore of skin seal cannula 10 and sealing the distal end of theballoon to the distal end of the cannula and sealing the proximal end ofthe balloon to the proximal end of the cannula, thereby creating aninflatable space between the cannula and the membrane. Alternatively, afully formed balloon bladder, comprising an inner and outer conicalmembranes sealed to each other at their distal and proximal ends can beprovided and fixed to the inner bore of the cannula. The overall shapeof the balloon will be conical, funnel shaped, or flared to match theshape of the inside of the skin seal. While one balloon is depicted ineach of the figures, two or more balloons may be used to guard againstthe possibility of rupture and loss of insufflation pressure during anoperation, or to facilitate manufacture, or to facilitate use of theskin seal with particular tools. A membrane seal may provided at anycross sectional plane, within the skin seal, to guard against loss ofinsufflation pressure.

FIG. 6 shows the inflatable skin seal with the membrane in its inflatedcondition. The squeeze pump 25 is used to force air in the space betweenthe bladder 20 and the wall of the cannula, causing the membrane toinflate within the cannula. The inflated membrane can be inflated untilit completely obstructs the inner bore of the cannula and provides anairtight seal between the distal and proximal ends of the cannula. Thecannula can be thin-walled and flexible enough to expand, as well,thereby further improving the seal between the cannula and the skinincision. As shown in FIG. 6a, the membrane need not extend for the fulllength of the cannula, but may instead be sealed to the inner bore atvarious points inside the cannula. The cannula in FIG. 6a has a balloon20 only in the conical inner bore of the proximal section of thecannula, and this facilitates use of graspers, scissors, and other suchinstruments which might pinch the balloon when operated, orunnecessarily reduce the internal diameter of the narrowest portion ofthe cannula. As shown in FIG. 6b, the wall of the cannula may be madeflexible enough to expand outward when the skin seal is inflated, sothat any gaps or looseness in the seal between the outside of the skinseal, and the skin incision are closed by the expansion of the outerwall 22 of the skin seal.

FIG. 7 shows the view of the inflated membrane viewed from the proximalend of the cannula. The membrane naturally bulges in two or more radialsections or segments 27 to fill the lumen of the cannula. The expansionof the balloon sections need not be controlled, but may be controlled tofacilitate operation of graspers or other hinged and pinching tools. Forexample, the application of restrictors comprised of thickened stripsalong the length of the membrane, shown in FIG. 7a, may be applied tothe membrane to inhibit expansion along the strip. Wire bands, plasticbands, or a line of adhesive gluing the balloon membrane to the skinseal may also be used to prevent expansion of the membrane along alongitudinal line of the membrane extending from the proximal end (ornear the proximal end) to the distal end (or near the distal end) of thefunnel. In this manner, a uniform expansion can be obtained with themembrane expanding from the walls of cannula to meet along a uniformplane. A pinching tool used in the cannula can be opened and closedalong the plane defined by the inflated balloons, and the balloon willpliantly close upon the lumen, but allow the pinching tool to open andclose with less chance of pinching and cutting the balloon. As shown inFIG. 7b, the inflatable membrane 20 may be placed on the inner bore ofthe skin seal in an eccentric manner, covering only a portion of theinner wall of the skin seal. FIG. 7c shows the eccentric inflatablemembrane in its inflated state.

FIG. 8 shows the skin seals 28, 29, and 30 with the balloon membranesinflated. Skin seal 28 has the funnel shape described above. A pair ofnormal surgical scissors, such as Metzenbaum scissors 31, is insertedthrough one skin seal 28 and a pair of normal surgical graspers 7(examples include Kelly clamps, Kelly placenta forceps, and Mayo clamps)is inserted through the skin seal cannula 29 to perform operationsbeyond the distal tip of the cannula. The skin seals are shown screwedinto incisions through skin 32 and subcutaneous fat 33, and they mayalso extend through the peritoneum or other tissue when appropriate tothe operation. An endoscope or laparoscope 34 which can be insertedthrough one skin seal to provide a view of the procedure is shown in thecentral skin seal 30. Because the balloon is pliable and conforms aroundany device within the skin seal, the graspers may be manipulated insidethe cannula without breaking the insufflation seal. As the graspers 7are manipulated, the membrane conforms around graspers, but yields toallow the graspers to be opened, closed, twisted, pushed, and pulledwithin the skin seal without substantially degrading the seal created bythe membrane. It should be noted that a perfectly airtight seal is notnecessary, and some leakage of insufflation gas or fluid is acceptable,so long as insufflation gas or fluid can be injected at a ratesufficient to make up for any loses. Where the cannula itself is made ofa soft pliant material such as latex rubber or silicone rubber, theforceps may be manipulated even further, and deformation of the skinseal 28 will permit a wider range of motion for the forceps. Skin seal28 is shown with a pair of conventional surgical scissors 31 or shearsdisposed through the skin seal. The scissors may be opened wide, asshown, and the distal or proximal end of the skin seal will yield andflare out to allow operation of the scissors through their full range ofmotion and opened through the full throw (the “throw” referring to thelength of arc 35 over which the graspers or scissors may be opened) ofscissors 31 or graspers, as illustrated by flared distal portion 36 ofskin seal 28.

It will be readily appreciated that such operation would not be possibleusing standard cannulas. The normal surgical tools are much easier touse than the long laparoscopic instruments shown in FIG. 2. Also, thetools can be much larger and have much larger operating implements. Forexample, the cutting edges of scissors 31 are much longer that cuttingedges on laparoscopic scissors and can cut much more quickly. A commonmethod of dissecting tissue with normal scissors is to pierce connectivetissue with the closed scissors and open the scissors, operating thescissors in backwards fashion, so that the dull outer edges of thescissors pull connective tissue apart. This can be done very quicklyusing the skin seals 29 and 30, as compared to slow and tedious snippingrequired when using long laparoscopic instruments.

Placement of the skin seals may be facilitated with special bluntobturators shown in FIGS. 9, 10, and 11. The blunt obturator 37 providessupport for the skin seal as it is pushed and screwed into the incision.The blunt obturator comprises a peg 38 with an outer contour whichmatches the inner bore of the skin seal, a handle 39, a finger gap 40,and a blunt tip 41. The tip may be blunt and rounded, or it may be sharpand pointed, as illustrated by the sharp pointed trocar type tip 42 inFIG. 10, in which case the sharp point 42 can puncture body tissue. Theobturator is placed inside the skin seal as shown in FIG. 11, and theassembly is screwed into the body as a unit. After the skin seal is inplace, the obturator is removed to allow insertion of other devices intothe skin seal. The finger gap 40 leaves some space for the surgeon topush against the flange of the skin seal while pulling the handle 39,thus avoiding the possibility that the skin seal will be pulled out ofthe body with the obturator 37. Because the obturator fits tightlyinside the skin seal to give it support during insertion, it mayinadvertently become sealed to the inside of the skin seal, especiallyif there is any leakage of body fluids or water into the skin seal. Anyexcessive force required to pull out the obturator could result inpulling the screw skin seal out of the skin incision. To prevent theneed for such excessive force, the portion of the obturator which fitsinside the skin seal may be provided with vacuum breakers in the form ofscored lines or channels 43, circumferential grooves 44, or a roughenedsurface to prevent a vacuum from forming between the skin sealinflatable membrane. The scoring or roughening may take any form.

FIG. 12 shows another embodiment of the skin seal in which the balloonis enlarged so that it expands outside the lumen of the skin seal. Theskin seal 45 shown in FIG. 12 includes a dumbbell shaped balloon 46. Theshape of the balloon may variously be described dog bone, bowtie,dumbbell, or butterfly shaped. The balloon 46 has a lumen 47 extendingthrough the balloon and can be provided with a rigid cannula segment orstiffener tube 48 disposed within the balloon. The stiffener tube needonly be stiff enough to provide support for the balloon duringplacement, so it is stiff in relation to the balloon membrane, but may,in fact, be very flexible and can be made of any plastic or elasticmaterial or other materials suitable for the inflatable membrane.

The balloon may be formed by sealing together an inner balloon tube 49and an outer balloon membrane 50. An inflation port 51 is provided onthe outer dumbbell portion, but may also be provided on the waistportion 52 or even the inner dumbbell. When used during insufflation, aninflation port may be provided on the inner dumbbell in form of a simpleairway provided in the inner dumbbell that allows insufflation gas toenter the balloon from the insufflated space. In this manner, the needfor a separate source of inflation gas or fluid is avoided.

The outer balloon membrane may be made of two or more pieces to createany desired outer shape. As shown in FIG. 13, the outer balloon membranehas an oval outer shape when inflated. The balloon may be provided withany other useful shape and may be round or toroidal, or oval, as shown.The balloon is formed of two pieces 53 and 54 that are heat sealed orsealed with adhesive along the seam 55. FIG. 13 also illustrates thatthe inner balloon tube 49 fits inside the lumen of the stiffener tube 48while the outer balloon surrounds the stiffener tube. FIG. 15 shows anexploded view of the device with butterfly shaped balloon membranes 53and 54, the tubular balloon membrane 47 extending across the “wingspan”or major length of the butterfly shaped membrane, and the stiffener tube48 surrounding the tubular balloon membrane 47. With the tubular balloonmembrane and the stiffener tube sandwiched between the butterfly shapedballoon membranes, the edges of the butterfly shaped membranes aresealed together, and the ends of the tubular balloon membrane are sealedto the edge of the butterfly shaped membranes at the middle of the outeredge of the wings, thereby forming a single balloon with an overallbutterfly shape and a through hole extending across the wingspan. Theballoon can be made of any suitable material, including polyethylenes,polyamide, polyurethanes, latex, or silicone rubber. The balloon may beelastic or nonelastic. The various pieces may be made of differentmaterial, for example the inner balloon tube may be made of an elasticmaterial, and the outer balloon membranes may be made of nonelasticmaterial.

The stiffener tube 48 may be a straight length of tube or it may befunnel shaped like the screw skin seals described above. The stiffenertube provides columnar support for the device so that it can be pushedthrough an incision in the skin. The stiffener tube may be made of anysuitable material, including any material previously mentioned above andany material previously used for cannulas and trocars. The length of thestiffener tube is chosen to approximate the thickness of the skin andfat layers 32 and 27, and is preferably slightly shorter than thethickness of the skin and fat layer. The stiffener tube may be disposedinside the balloon pieces without being sealed in any way to the balloonpieces, or it may be sealed to either the inner or outer balloon pieces.

The inner balloon tube may be sealed along a circumference of the tubejust as the balloon membrane of FIGS. 5 and 6 is sealed to the threadedskin seal, and it may be sealed to the stiffener tube along one or morelongitudinal lines as shown in FIG. 7a. The inner balloon may also beprovided with thickened longitudinal portions, metal, or plastic bands,etc., as described in reference to FIG. 7a to control inflation andencourage inflation toward a uniform plane in the center of the lumen.Also, the inner balloon 49 may be sealed to the stiffener tube 48 atboth ends of the stiffener tube, as is the balloon membrane of thethreaded skin seal, and inflated through an optional airway 56. Theouter balloon pieces may be sealed to the outside of the stiffener tube,either by sealing the entire waist portion to the stiffener tube, or bydispensing with the waist portion and sealing the dumbbell portion ofthe balloons to the ends 57 and 58 of the stiffener tube, as shown inFIG. 14.

In use, the distal end of the deflated balloon is tucked into or pulledinto the stiffener tube, as shown in FIG. 16. An obturator, trocar, orcannula 59 is placed inside the stiffener tube 48 to facilitateinsertion of the skin seal into an incision. The cannula 59 is pushedinto the incision along with the skin seal that rides over the cannula.With the cannula 59 in the incision, the skin seal 45 can be pushed overthe cannula and into the incision. After the skin seal has been insertedinto the incision, the cannula may be removed leaving the skin seal inplace. Then the balloon can be inflated, as shown in FIG. 17. When theballoon is inflated, as shown in FIG. 17, the outer dumbbell portion 60is inflated while the inner dumbbell portion 61 expands out of thestiffener tube and into the body and inflates to re-establish thedumbbell shape. When the balloon is inflated further, the expandingdumbbells clamp down on skin 32, fat 33, and other tissue trappedbetween the inner balloon portion 61 and outer balloon portions 60. Thestiffener tube 48 prevents the inner balloon tube from collapsing at thewaist 52, but the inner balloon may expand to fill the lumen or throughhole 47. The inner balloon tube 49, when inflated to fill the throughhole, acts as a seal for any device such as the endoscope 34 placedthrough the lumen, as shown in FIG. 17. A trocar or cannula may beinserted into the body through the lumen of the skin seal to allowinserting of laparoscopic instruments through the cannula orlaparoscopic instruments, and normal surgical instruments may beinserted through the skin seal, as shown in FIGS. 17a and 17 b, wherethe inner balloon tube expands to conform around the instruments. FIG.17a shows the same skin seal with a pair of normal graspers used foropen surgery inserted into the body through the skin seal. FIG. 17bshows the skin seal inflated so that the inner balloon tube 49completely fills the lumen of the skin seal, thus maintaining theinsufflation of the working space below the skin seal.

In another embodiment, only the inside or distal end of the balloonexpands outside the skin seal. As shown in FIG. 18, the stiffener tubeis provided with a flange 62 on the proximal end. The inner balloon tubeis sealed to the inside of the stiffener tube at the proximal end of thetube. The outer balloon portion is sealed to the outside surface of thestiffener tube. The inner or distal dumbbell portion is expanded insidethe body, and inflation of the distal dumbbell portion clamps the skinand fat between the flange and the distal balloon. When the centrallumen is not occupied by an instrument, the balloon can be inflated sothat the inner balloon tube expands into the central lumen andestablishes a seal between the insufflated work space and the outside ofthe body. The seal can be supplied in a variety of sizes, with stiffenertubes of various sizes to match commercially available trocars, cannulasand laparoscopic instruments. The size of the balloon and the length ofthe stiffener tube can be varied to fit incisions of various sizesrequired by the many different operations with which the skin seal canbe used. The skin seal may be used for laparoscopic access in anyprocedure, and can also be used to compress bleeding incisions and plugunneeded incisions during laparoscopic surgery.

The skin seals described above can be used for any endoscopic orlaparoscopic surgery to permit use of normal surgical instruments, i.e.,ordinary open incision surgical instruments. While the skin sealsdescribed above are useful in procedures requiring insufflation, theymay also be used in other endoscopic or laparoscopic procedures. The useof the skin seal in any endoscopic or laparoscopic procedures will allowdeployment of normal surgical tools while protecting the area of theincision from trauma caused by the operation of the surgicalinstruments. Where insufflation or flushing is required, the bladder inthe skin seal may be inflated to prevent undesired flow out of thecannula. Also, although the skin seal described above has been describedin the best known embodiments, fabricated with suitable materials to theinventors, the particular materials and shapes depicted in theillustrations may be altered and improved upon without departing fromthe inventions as claimed. It is specifically contemplated that thematerials be improved upon. Furthermore, although the devices have beendescribed in relationship to surgery requiring insufflation andendoscopic or laparoscopic surgery, the claimed devices and methods maybe used in surgical and nonsurgical applications wherever the featuresof these device and methods prove beneficial.

What is claimed is:
 1. A surgical access device comprising: a flexibletube having a proximal end, a distal end and an inner bore, and a flangeon said proximal end; a balloon bladder inserted into the bore of theflexible tube, said balloon bladder comprising: an inner membrane with adistal end and a proximal end; an outer membrane with a distal end, aproximal end and an inflation opening; and an inflation portcommunicating with said inflation opening on the outer membrane of theballoon bladder, wherein the proximal end of the inner membrane issealed to the proximal end of the outer membrane and the distal end ofthe inner membrane is sealed to the distal end of the outer membrane. 2.A surgical access device comprising: a flexible tube having a proximalend, a distal end and an inner bore, and fastening means comprisingprotrusions on the outer surface of said flexible tube; a balloonbladder inserted into the bore of the flexible tube, said balloonbladder comprising: an inner membrane with a distal end and a proximalend; an outer membrane with a distal end, a proximal end and aninflation opening; and an inflation port communicating with saidinflation opening on the outer membrane of the balloon bladder, whereinthe proximal end of the inner membrane is sealed to the proximal end ofthe outer membrane and the distal end of the inner membrane is sealed tothe distal end of the outer membrane.
 3. A surgical access devicecomprising: a flexible tube having a proximal end, a distal end and aninner bore, and fastening means comprising screw threads on the outersurface of said flexible tube; a balloon bladder inserted into the boreof the flexible tube, said balloon bladder comprising: an inner membranewith a distal end and a proximal end; an outer membrane with a distalend, a proximal end and an inflation opening; and an inflation portcommunicating with said inflation opening on the outer membrane of theballoon bladder, wherein the proximal end of the inner membrane issealed to the proximal end of the outer membrane and the distal end ofthe inner membrane is sealed to the distal end of the outer membrane. 4.A surgical access device comprising: a flexible tube having a proximalend, a distal end and an inner bore, and fastening means comprisingcircumferential ribs on the outer surface of said flexible tube; aballoon bladder inserted into the bore of the flexible tube, saidballoon bladder comprising: an inner membrane with a distal end and aproximal end; an outer membrane with a distal end, a proximal end and aninflation opening; and an inflation port communicating with saidinflation opening on the outer membrane of the balloon bladder, whereinthe proximal end of the inner membrane is sealed to the proximal end ofthe outer membrane and the distal end of the inner membrane is sealed tothe distal end of the outer membrane.
 5. A surgical access devicecomprising: a flexible tube having a proximal end, a distal end and aninner bore, and fastening means comprising grooves on the outer surfaceof said flexible tube; a balloon bladder inserted into the bore of theflexible tube, said balloon bladder comprising: an inner membrane with adistal end and a proximal end; an outer membrane with a distal end, aproximal end and an inflation opening; and an inflation portcommunicating with said inflation opening on the outer membrane of theballoon bladder, wherein the proximal end of the inner membrane issealed to the proximal end of the outer membrane and the distal end ofthe inner membrane is sealed to the distal end of the outer membrane. 6.A surgical access device comprising: a conical flexible tube having aproximal end, a distal end and an inner bore; and a balloon bladderinserted into the bore of the flexible tube, said balloon bladdercomprising: an inner membrane with a distal end and a proximal end; anouter membrane with a distal end, a proximal end and an inflationopening; and an inflation port communicating with said inflation openingon the outer membrane of the balloon bladder, wherein the proximal endof the inner membrane is sealed to the proximal end of the outermembrane and the distal end of the inner membrane is sealed to thedistal end of the outer membrane.
 7. The device of claim 6 wherein saidballoon bladder is conical.
 8. A surgical access device comprising: aflexible tube having a proximal end, a distal end and an inner bore; anda balloon bladder inserted into the bore of the flexible tube, saidballoon bladder comprising: an inner membrane with a distal end and aproximal end; an outer membrane with a distal end, a proximal end and aninflation opening; and an inflation port comprising a hole in the wallof the flexible tube communicating with said inflation opening on theouter membrane of the balloon bladder, wherein the proximal end of theinner membrane is sealed to the proximal end of the outer membrane andthe distal end of the inner membrane is sealed to the distal end of theouter membrane.
 9. A surgical access device comprising: a flexible tubehaving a proximal end, a distal end and an inner bore, and a flange onsaid proximal end of said flexible tube; an expandable membrane having aproximal end, a distal end, and a lumen extending therethrough, theexpandable membrane disposed coaxially within said inner bore of saidflexible tube, wherein the proximal and distal ends of the expandablemembrane are sealed to the flexible tube.
 10. A surgical access devicecomprising: a flexible tube having a proximal end, a distal end and aninner bore, and fastening means comprising protrusions on the outersurface of the flexible tube; an expandable membrane having a proximalend, a distal end, and a lumen extending therethrough, the expandablemembrane disposed coaxially within said inner bore of said flexibletube, wherein the proximal and distal ends of the expandable membraneare sealed to the flexible tube.
 11. A surgical access devicecomprising: a flexible tube having a proximal end, a distal end and aninner bore, and fastening means comprising screw threads on the outersurface of the flexible tube; and an expandable membrane having aproximal end, a distal end, and a lumen extending therethrough, theexpandable membrane disposed coaxially within said inner bore of saidflexible tube, wherein the proximal and distal ends of the expandablemembrane are sealed to the flexible tube.
 12. A surgical access devicecomprising: a flexible tube having a proximal end, a distal end and aninner bore, and fastening means comprising circumferential ribs on theouter surface of the flexible tube; and an expandable membrane having aproximal end, a distal end, and a lumen extending therethrough, theexpandable membrane disposed coaxially within said inner bore of saidflexible tube, wherein the proximal and distal ends of the expandablemembrane are sealed to the flexible tube.
 13. A surgical access devicecomprising: a flexible tube having a proximal end, a distal end and aninner bore, and fastening means comprising grooves on the outer surfaceof the flexible tube; and an expandable membrane having a proximal end,a distal end, and a lumen extending therethrough, the expandablemembrane disposed coaxially within said inner bore of said flexibletube, wherein the proximal and distal ends of the expandable membraneare sealed to the flexible tube.
 14. A surgical access devicecomprising: a conical flexible tube having a proximal end, a distal endand an inner bore; an expandable membrane having a proximal end, adistal end, and a lumen extending therethrough, the expandable membranedisposed coaxially within said inner bore of said flexible tube, whereinthe proximal and distal ends of the expandable membrane are sealed tothe flexible tube.
 15. The device of claim 14 wherein said expandablemembrane is conical.
 16. A surgical access device comprising: a flexibletube having a proximal end, a distal end and an inner bore; anexpandable membrane of a length less than the length of said flexibletube having a proximal end, a distal end, and a lumen extendingtherethrough, the expandable membrane disposed coaxially within saidinner bore of said flexible tube, wherein the proximal and distal endsof the expandable membrane are sealed to the flexible tube.
 17. Thedevice of claim 16 wherein the proximal and distal ends of theexpandable membrane are sealed to the bore of the flexible tube.
 18. Asurgical access device comprising: a flexible tube having a proximalend, a distal end and an inner bore, and a flange on said proximal endof flexible tube; an expandable membrane having edges, the expandablemembrane disposed within said inner bore of said flexible tube, whereinthe edges of the expandable membrane are sealed to the flexible tube;and an inflation port communicating with said expandable membrane.
 19. Asurgical access device comprising: a flexible tube having a proximalend, a distal end and an inner bore, and fastening means comprisingprotrusions on the outer surface of the flexible tube; an expandablemembrane having edges, the expandable membrane disposed within saidinner bore of said flexible tube, wherein the edges of the expandablemembrane are sealed to the flexible tube; and an inflation portcommunicating with said expandable membrane.
 20. A surgical accessdevice comprising: a flexible tube having a proximal end, a distal endand an inner bore and fastening means comprising screw threads on theouter surface of the flexible tube; an expandable membrane having edges,the expandable membrane disposed within said inner bore of said flexibletube, wherein the edges of the expandable membrane are sealed to theflexible tube; and an inflation port communicating with said expandablemembrane.
 21. A surgical access device comprising: a flexible tubehaving a proximal end, a distal end and an inner bore, and fasteningmeans comprising circumferential grooves on the outer surface of theflexible tube; an expandable membrane having edges, the expandablemembrane disposed within said inner bore of said flexible tube, whereinthe edges of the expandable membrane are sealed to the flexible tube;and an inflation port communicating with said expandable membrane.
 22. Asurgical access device comprising: a flexible tube having a proximalend, a distal end and an inner bore and fastening means comprisinggrooves on the outer surface of the flexible tube; an expandablemembrane having edges, the expandable membrane disposed within saidinner bore of said flexible tube, wherein the edges of the expandablemembrane are sealed to the flexible tube; and an inflation portcommunicating with said expandable membrane.
 23. A surgical accessdevice comprising: a conical flexible tube having a proximal end, adistal end and an inner bore; an expandable membrane having edges, theexpandable membrane disposed within said inner bore of said flexibletube, wherein the edges of the expandable membrane are sealed to theflexible tube; and an inflation port communicating with said expandablemembrane.
 24. A surgical access device comprising: a flexible tubehaving a proximal end, a distal end and an inner bore; an expandablemembrane having edges, the expandable membrane disposed within saidinner bore of said flexible tube, wherein the edges of the expandablemembrane are sealed to the flexible tube; and an inflation portcomprising a hole on the surface of the flexible tube communicating withsaid expandable membrane.
 25. A surgical access device comprising: aflexible tube having a proximal end, a distal end and an inner bore; anexpandable membrane having edges, the expandable membrane disposedwithin said inner bore of said flexible tube, wherein the edges of theexpandable membrane are attached to the flexible tube to form a seal;and an inflation port comprising an opening in the seal between theexpandable membrane and the flexible tube communicating with saidexpandable membrane.